Circulating water heater

ABSTRACT

In a circulating water heating system the circulating water is subjected by alternate expansion and contraction of a steam or gas volume to pressure pulses which cause the water to flow through the circulation system. In the heater the steam or gas volume is enclosed in an inner chamber which is actuated by a source of heat and which is in communication with an outer chamber to which the incoming and outgoing conduits of the circulation system are connected. The novel features of the invention reside in the provision of an inlet conduit to the heater which is directly connected to the junction between inner and outer chambers at the lower portion of the heater, while the outlet conduit is connected to the upper portion of the outer chamber and is provided with a check valve arrangement. The upper portion of the inner chamber, which contains the steam or gas volume is contained, is selectively connected to the outer chamber via a controllable valve arrangement.

United States Patent H 13,59s,0s9

[72] Inventor Erik Kenning Enskede,Sweden [21] AppLNo. 845,999 [22] Filed July30,1969 [45] Patented Aug.10, 1971 [73] Assignee AB Pulsvarme Nacka Sweden [54] CIRCULATING WATER HEATER 6Chims,21)rawing Figs.

[52] [1.8.01 122/165, 122/406 [51] lnLCl F22b7/00 [50] FieldotSearch 122/160, 165,155,406

[56] References Cited UNITED STATES PATENTS 2,074,948 3/1937 Sturgis 122/165 2,608,957 9/1952 Glawe 122/165 2,684,054 7/1954 Carson 122/155 3,358,651 12/1967 Maruyama ABSTRACT: In a circulating water heating system the circulating water is subjected by alternate expansion and contraction of a steam or gas volume to pressure pulses which cause the water to flow through the circulation system. In the heater the steam or gas volume is enclosed in an inner chamber which is actuated by a source of heat and which is in communication with an outer chamber to which the incoming and outgoing conduits of the circulation system are connected. The novel features of the invention reside in the provision of an inlet conduit to the heater which is directly connected to the junction between inner and outer chambers at the lower portion of the heater, while the outlet conduit is connected to the upper portion of the outer chamber and is provided with a check valve arrangement. The upper portion of the inner chamber, which contains the steam or gas volume is contained, is selectively connected to the outer chamber via a controllable valve arrangement.

FROM Z5 cation with the other water chamber, while the other water chamber is provided with inlet and outlet conduits which lead to and away from the water circulation system. A steam or gas volume contained in the upper portion of said ont water chamber is adapted during heating to be alternately ex )anded and contracted to provide a pulsating flow of the water through the heater.

The characteristic main features of the circulating water heater according to the present invention reside in the provision of two water chambers which are preferably annular and arranged one within the other around the source of heat. The inner water chamber is directly exposed to the heat source and has its lower portion in direct communication with the lower portion of the outer chamber. The height of the outer chamber is greater than the height of the inner chamber. The inlet conduit of the circulation system. is in open communication with the heater at the junction between the inner and the outer water chambers, while the outlet conduit leading to the circulation system is provided with a check valve arrangement and is connected to the upper end of the outer water chamber which extends above the inner water chamber. The steam or gas volume is contained in the upper portion of the directly heated inner water chamber.

The invention will now be more fully described in the fol- Iowingwith reference to the accompanying drawing which illustrates an embodiment, chosen by way of example, of the circulating water heater.

In the drawing:

FIG. I is a longitudinal section of the water heater;

FIG. 2 is a sectional view of the water heater of FIG. I looking in the direction of arrows 2-2.

In the drawing, 1 designates an annular shaped elongated outer water chamber having its lower portion in communication with a shorter inner water chamber 2 radially spaced from said outer water chamber 1. The heater is provided with a suitable inlet conduit 4 connected to the heater at the junction 3 between the two water chambers, and an outlet conduit 5 connected to the upper end of the outer water chamber 1. The interconnected water chambers 1 and 2 are enclosed in an insulated shell 6 which at the lower end houses a gas or oil burner 7 with control, ignition and supervision apparatus 8, 9 and I0, respectively. The upper end of shell 6 has an outlet opening 11 for exhaust gases and the lower end of shell 6 has inlets 12 for entry of combustion air. Mounted in the interior of the cylindrical space defined by the inner water chamber and adapted for the flow of the exhaust gases therethrough, is a helical plate I3 which has its vertical edges joined to the interior wall of chamber 2 for facilitating the heat transfer from heat source 7 to chamber 2. Flanges I4, which are disposed along the interior wall of outer water chamber I perform a similar function.

The inlet conduit 4 is constantly open and is connected to the return conduit of the central heating system in which the water heater is incorporated, while the outlet conduit 5 which is connected to the riser of the heating system is provided with a check valve arrangement IS. The heating system may include one or more radiators 20, connected between the conduit 4 and valve 15.

As another application, the device of FIGS. I and 2 may be employed as a means for pumping heated water to a ut'lization means such as a shower, a washing machine, a sink, or other like utilization means.

The upper end of the inner water chamber 2 is provided with a passage 16 which connects the inner water chamber 2 to the outer water chamber 1. The passage 16 has a throttle or control valve 17 which is adjustable by means of a handwheel 18 positioned outside the shell 6. The valve I7 is a needle-type valve and permits a very exact control of the flow through the passage I6. The valve stem I9 extends through a seal 21 in the wall of outer water chamber I to prevent leakage.

The circulating water heater functions as follows:

When the burner 7 is started both water chambers I and,2 are completely filled with water. The inner water chamber 2, however, is very rapidly heated to cause steam to be generated in the upper region 22 of chamber 2. When the steam pressure exceeds the static pressure in the system there will momentarily occur a displacement of heated water through the outlet 5 past the check valve 16. The heated water is not forced out through the inlet conduit 4 due to the fact that the static pressure therein is higher than that in the outlet conduit 5. In order that the water urged out of the heater under pressure shall choose the correct outlet, the check valve is designed to present a very small resistance. In the heater according to the invention, this has been solved by forming the valve member from two very thin soft halves of rubber or like material which normally tend to engage one another but when acted upon by the water pressure are separated and allow water to flow through the opening fonned by their separation. By reason of the static pressure in the inlet conduit hot water will be forced out by the steam for only a brief moment in order to maintain balance in the system, and then cold water will enter the water chambers to occupy the place of the water just emitted from the heater. The cold water entering conduit 4 causes condensation of part of the steam. After the heating has proceeded for still some time the steam pressure again rises whereby the cycle is repeated.

The passage 16 having the control valve I7 arranged to prevent the steam pressure from rising in an uncontrollable fashion in the inner water chamber 2, since uncontrolled steam generation in the presence of a large fuel supply might lead to so high a steam pressure that the steam would expel all water from the water chambers. By setting the control valve 17 in such a manner that a certain amount of steam escapes directly into the outer water chamber one will have the safety that the steam pressure does not become too high. The steam flowing into the outer water chamber also improves the circulation by carrying along hot water in an upward direction through the water chamber towards the outlet 5.

Several modifications are possible within the scope of the appended claims.

I claim:

I. A water heater for pumping water including:

a heat source;

a first annular shaped water chamber defining a hollow central opening and being positioned to be directly heated by said heat source;

a second annular shaped water chamber surrounding said first water chamber and having its lower portion joined and in communication with the lower portion of said first chamber;

said second chamber having a height greater than said first chamber and having an inlet conduit communicating with the second chamber at its lower end and an Outlet conduit communicating with said second chamber at its upper end;

said heat source being positioned below said central opening to generate steam in the upper portion of said first chamber, whereby the expansion of said steam causes water to be urged downwardly from said first chamber to enter said second chamber through their joined lower portions causing water to be expelled under pressure from said outlet conduit and thereby allow water supplied to said inlet conduit to enter into the region of the communicating junction between said first and second chambers;

a check valve assembly being positioned within said outlet conduit for enabling the passage of water expelled from the upper end of said second chamber and for preventing the passage of water into said second chamber from said outlet conduit.

2. A heater as claimed in claim 1, further comprising a control valve selectively coupling the upper end of said first water chamber to an intermediate portion of said second water chamber for controlling the pressure and flow of the steam generated during heating in the upper portion of said first water chamber so that the steam pressure is maintained within such limits relative to the static pressure in the system that the expanding steam is momentarily capable of urging heated water past the check valve assembly into the outlet conduit, and whereby the pressure balance of the system is reestablished by the'entrance of water through said inlet conduit into the lower portion of the first and second water chambers to cause contraction of the steam, and to be subsequently heated until the steam pressure has again reached'the value necessary for expelling water through said outlet conduit.

' 3. A water circulation system employing the heater of claim 1 and being comprised of a heated water utilization means coupled between said inlet and outlet conduits for circulating the water through said system.

is twisted in a helical fashion. 6. The heater of claim 4, wherein the inner wall ofsa'id second chamber defines a hollow opening communicating with the opening in said first chamber;

a plurality of heat conductive plates being joined to said second chamber inner wall to facilitate heat transfer from said heat source to said second chamber;

said plurality of heat-conductive plates being further removed from said heat source than said first heat-conductive plate 

1. A watEr heater for pumping water including: a heat source; a first annular shaped water chamber defining a hollow central opening and being positioned to be directly heated by said heat source; a second annular shaped water chamber surrounding said first water chamber and having its lower portion joined and in communication with the lower portion of said first chamber; said second chamber having a height greater than said first chamber and having an inlet conduit communicating with the second chamber at its lower end and an outlet conduit communicating with said second chamber at its upper end; said heat source being positioned below said central opening to generate steam in the upper portion of said first chamber, whereby the expansion of said steam causes water to be urged downwardly from said first chamber to enter said second chamber through their joined lower portions causing water to be expelled under pressure from said outlet conduit and thereby allow water supplied to said inlet conduit to enter into the region of the communicating junction between said first and second chambers; a check valve assembly being positioned within said outlet conduit for enabling the passage of water expelled from the upper end of said second chamber and for preventing the passage of water into said second chamber from said outlet conduit.
 2. A heater as claimed in claim 1, further comprising a control valve selectively coupling the upper end of said first water chamber to an intermediate portion of said second water chamber for controlling the pressure and flow of the steam generated during heating in the upper portion of said first water chamber so that the steam pressure is maintained within such limits relative to the static pressure in the system that the expanding steam is momentarily capable of urging heated water past the check valve assembly into the outlet conduit, and whereby the pressure balance of the system is reestablished by the entrance of water through said inlet conduit into the lower portion of the first and second water chambers to cause contraction of the steam, and to be subsequently heated until the steam pressure has again reached the value necessary for expelling water through said outlet conduit.
 3. A water circulation system employing the heater of claim 1 and being comprised of a heated water utilization means coupled between said inlet and outlet conduits for circulating the water through said system.
 4. The heater of claim 1, wherein the interior wall of said first chamber defines a hollow opening for the passage of air or ocher gases therethrough; a first heat-conductive plate positioned within said hollow opening and being joined to said first chamber inner wall to facilitate heat transfer from said heat source to said first chamber.
 5. The heater of claim 4, wherein said heat-conductive plate is twisted in a helical fashion.
 6. The heater of claim 4, wherein the inner wall of said second chamber defines a hollow opening communicating with the opening in said first chamber; a plurality of heat conductive plates being joined to said second chamber inner wall to facilitate heat transfer from said heat source to said second chamber; said plurality of heat-conductive plates being further removed from said heat source than said first heat-conductive plate. 